feat: added draft functionality for comment and responses

[sundasnoreen12]

INF-1444

Description

Learners using the discussion board have faced a frustrating issue: losing their work when switching tabs and returning to the post. This can be especially disheartening for those writing lengthy comments or responses. The issue occurs specifically while writing comments or responses on posts.

Solution

Draft Feature: Offering a draft functionality where users can save unfinished posts and return to them later. The draft only be saved on the frontend and are lost on page reload.

Screenshots/sandbox (optional):

https://www.loom.com/share/fa0007a967ea406f89835409009dd3b1?sid=72cdf8c3-2e9f-4816-ba62-d7b991b5872b

Merge Checklist

• [ ] If your update includes visual changes, have they been reviewed by a designer? Send them a link to the Sandbox, if applicable.
• [ ] Is there adequate test coverage for your changes?

Post-merge Checklist

• [ ] Deploy the changes to prod after verifying on stage or ask @openedx/edx-infinity to do it.
• [ ] 🎉 🙌 Celebrate! Thanks for your contribution.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 97.01493% with 2 lines in your changes missing coverage. Please review.

Project coverage is 93.16%. Comparing base (422fbf6) to head (13a8a17).

Files	Patch %	Lines
src/discussions/post-comments/data/hooks.js	97.29%	1 Missing :warning:
src/discussions/utils.js	75.00%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #727 +/- ## ========================================== + Coverage 92.88% 93.16% +0.28% ========================================== Files 160 160 Lines 3329 3396 +67 Branches 888 917 +29 ========================================== + Hits 3092 3164 +72 + Misses 219 214 -5 Partials 18 18 ```

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